The present invention relates generally to fire-barriers and more particularly to tested, rated, and certified mirrored and two-sided fire-barriers for use in expansion-joint spaces between structural units.
The background information discussed below is presented to better illustrate the novelty and usefulness of the present invention. This background information is not admitted prior art. The particular versions of the invention as described below are provided, in part, as illustrative and exemplary, thus, the described versions should not be taken as limiting.
Modern building codes require that stresses experienced by buildings from extreme and/or repetitive changes in temperature, the force of high winds impinging on the building, multi-directional forces due to seismic events, settling of subsoil, building remodels, and excavation on or near the site, for example, be taken into account in the building design. Thus, to accommodate these stresses, buildings now must be constructed with a code-mandated space between adjacent wall, floor, and/or ceiling units. These spaces, referred to as “expansion-joint spaces,” allow differential building motions to take place without risking damage to the whole structure.
However, while expansion-joint spaces improve the life-time integrity of buildings and other structures, they also present a major risk in the event of a fire as the mandated expansion-joint spaces can act as chimney flues providing pathways for gases, flame, and smoke to spread rapidly throughout a structure. To counter the chimney flue effect, building codes for commercial structures require fire-barriers to be installed in the expansion-joint spaces to prevent or to reduce the rate of flames and smoke passing through the joints into adjoining areas. Fire-barriers sometimes referred to as “fire-stops,” protect both the building and the inhabitants of the building by extending the time available for inhabitants to leave the building and for fire-fighters to get to the fire.
To be fire barrier functional, fire-barriers are legally mandated to be tested, rated, and certified. There are two currently mandated tests. One measures the ability of a fire-barrier to maintain its structural integrity under compressional and tensional motion, such as the kind of forces a building goes through during an earthquake. This test is referred to as the “cycle” test and its parameters are specified by ASTM 1399. The other test is referred to as the “fire” or “burn” test and its parameters are specified by UL 2079. The two tests are conducted in sequence. A fire-barrier is first cycled between forces of compression and tension 500 times and then, if the barrier passes that test, it is placed into a furnace where it is tested for its ability to resist and prevents flame, heat, and gases from passing through the barrier. Once it passes both tests, the testing agency grants the barrier a Certificate of Listing and the barrier is considered certified.
A different of stress suffered by fire-barriers is exposure to moisture. Once a fire-barrier becomes wet it loses its certification. Drying the barrier does not restore the certification; once the barrier has been wet it is not considered effective. It is difficult, if not impossible, to prevent moisture from reaching barriers. Public facilities such as open stadiums are regularly subjected to the effects of rain and snow as parts of these facilities are frequently, if not always, open to the effects of rain and snow. More enclosed areas are subjected to water and liquids used for cleaning. The integrity of fire-barriers installed in hospitals, schools, sports facilities, hotels, air ports, and high-rise buildings is threatened by copious amounts of water used for cleaning purposes, especially for floor cleaning, on a daily or even more frequent basis. Fire-barrier failure in any facility, especially in facilities with bed-bound occupants, is likely to result in unnecessary hazards to, and even to loss of, life. The importance of correctly designed, installed, tested, and maintained fire-barriers is increasingly recognized by building officials, owners, insurance companies, contractors, and the public.